Low impact switch apparatus

ABSTRACT

A platform of the type holding a plurality of normally-open electric switches in position for activation of a selected individual switch by application of a force in a direction normal to a surface of the switch by a portion of a human body. An exemplary platform according to the invention forms a dance platform on which a user steps to activate switches in accordance with instructions viewed on a video display device. A joining structure may by used to hold two platforms in a side-by-side competition arrangement. A security vault may be affixed to structure associated with platform to resist theft of a commercially available game controller adapted to operate the video display and to receive switch input from a platform. Certain aspects of the invention include one or more, typically inert, practice platforms structured to represent the user interface surface of an activatable platform. A method for using a system of active and inert platforms is also disclosed.

RELATED APPLICATIONS

This application is a divisional from U.S. utility application Ser. No.10/879,439, filed Jun. 29, 2004 now U.S. Pat. No. 7,122,751, titled“SWITCH APPARATUS”, which claims the benefit under 35 U.S.C. 119(e) ofthe filing date of Provisional Application Ser. No. 60/536,896 filedJan. 16, 2004, titled “DANCE PLATFORM”.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to platforms operable to hold normally-open ornormally closed switches in a fixed orientation in an electric circuitfor activation of a selected switch by application of a force onto theswitch by a portion of a human body.

2. State of the Art

Platforms of the type holding normally-open switches in a fixedarrangement for activation of a selected switch by placements of auser's foot are disclosed in U.S. Pat. Nos. 6,227,968 and 6,410,835 toSuzuki et al. Such platforms are used commercially in a competitive gameformat, and may be characterized as dance platforms. A dance platformincludes nine tiles that are approximately 11 inches square; arranged inthree rows of three tiles each, in a tic-tac-toe type pattern. Each tilerepresents a place for a user, or platform operator, to stand. Indicia,such as arrows, are displayed on certain tiles. The operator of such adance platform tries to stand on indicia in accordance with instructionsvisible on an associated video display. The video display is mounted forviewing by the platform operator. In a competitive arrangement, a pairof dance platforms are disposed in side-by-side harmony so that a pairof users can see the video display at the same time. An output caused byswitch activation is provided from each platform as feedback to acontroller operable to evaluate a user's performance.

In one commercial arrangement providing competitive dance platformsoperable as a game, the platforms are disposed in association with avideo display and controller substantially as a single unitary structurein an arcade setting. Such an arrangement provides a measure of theftresistance to individual components of the system, but consequentlyreduces portability of the system.

Software has been commercially developed for use with commerciallyavailable game consoles or controllers, such as the Sony PlayStation IIand Microsoft Xbox, for individual use in a home environment. Portabledance platforms configured to interface with such game controllers toreplicate an arcade gaming experience are commercially available fromseveral sources. It is believed that a manufacturing Company located inChina is distributing dance platforms through a plurality of businessnames, including My-My Box; Red Octane; and Buynshop.

Commercially available dance platforms include types that may be eitherrigid or roll-up. Rigid platforms may be characterized as includingstructure operable to maintain their planar shape, and to hold theirswitches in a fixed relative orientation. Typically, switch elements ofsuch platforms are mounted on a substrate made from wood. Rigidplatforms tend to be heavier, which reduces ease of transportability.Switches of certain rigid platforms include a plexiglass plastic tile,which carries a sheet of electrically conductive foil, suspended over acopper coil element. The tile is suspended about its perimeter by a rimof open cell foam adapted to bias the tile (and its conductive foil)apart from the copper coil. When a user steps on the tile, the foil isdisplaced into bridging contact across positive and negative terminalsof the copper coil element. Unfortunately, the foil often flakes off,leaving a bridge on the copper coil, and results in a “stuck button”.The plexiglass plastic tiles also tend to break under extended use ofthe platform. Furthermore, the open cell foam wears out over time,resulting in a “stuck button” or a button that can misfire or send afalse signal.

Platforms of the roll-up type tend to be light in weight, and by rollingup, can easily be transported and stored in a reduced-size volume.Companies selling roll-up type platforms include: Naki International,having a place of business at 5101 Commerce Drive, Baldwin Park, Calif.91706; Mad Cats, having a place of business at 7480 Mission Valley Road,Suite 101, San Diego, Calif. 92018; and Pelican, having a place ofbusiness at 181840 East 27th Street, Vernon, Calif. 90058.

Roll-up platforms typically include a pair of electrically conductivefilm elements spaced apart by a thin (perhaps ¼ inch) layer ofperforated open cell foam. Such platforms tend to be more delicate, andtypically are operated without shoes on a user's feet. When a user stepson a switch portion of such a platform, the conductive elements makecontact at perforation locations under the user's foot. Unfortunately,the open cell foam wears out under repeated use, causing false signals.The conductive film elements also wear out, flake apart, and can causemisfire signals. Certain competitive moves cannot be performed on aroll-up platform, because the platform cannot maintain a planar shapeunder certain user movements. In fact, operating a roll-up platform atan advanced level of play can cause the foam and switch elements tomigrate or move with respect to an opaque covering. Consequently, a userstepping on a valid switch location may inadvertently cause a signalfrom a neighbor switch that has migrated.

It is important to a user of a platform for that platform to beaccurate, so that no false signals are sent to a controller. Switches ina platform desirably are responsive to a user's contact, fast acting,and reliably and repeatably activated by a user properly engaging aswitch portion of the platform. Preferred dance platforms provide a“feel” to a user in harmony with the “feel” of an arcade game sold inthe United States by the Konami Arcade Division since 2001 and known bythe name “Dance Dance Revolution” or DDR.

It would be an improvement in the art to provide a switch carryingplatform operable in various physical therapies. A further advance wouldprovide a portable platform having a responsive “feel” and reliablenormally-open switch action. An additional advance would provide a danceplatform causing a reduced repetitive stress impact on a user. A furtheradvance would provide structure to resist injury to a user arising fromthe user stepping onto an edge portion of the platform. Another advancewould provide structure to couple a pair of platforms in a side-by-sidearrangement for competitive operation of the pair of platforms whileoperators of the platforms make reference to a single video display. Astill further advance would provide a reduced-cost practice platform.Yet another advance would provide a system for obtaining exercise in agroup setting. A still further advance would provide a platform and atheft resistant arrangement for an associated controller.

BRIEF SUMMARY OF THE INVENTION

The present invention provides an apparatus and method to provide aninstruction set to a user, and to measure a response of that user to theinstruction set. The invention can be embodied in a platform of the typeholding a plurality of normally-open electrically conductive switches.It is within contemplation to provide alternative platforms with similarconstruction, but having normally-closed switches.

In general, certain currently preferred embodiments of a platform areconfigured and arranged to permit closing of an individual selectedswitch by application of a force in a direction approximately normal toan activation surface of the selected switch by a portion of a humanbody. In one preferred configuration, a platform is structured fordisposition in a substantially horizontal orientation to permit closingof individual of said switches by a foot of a user. Such a horizontalplatform sometimes is characterized as a dance platform. An alternativeplatform is structured for disposition in a substantially verticalorientation to permit closing of individual of said switches by a handof a user. However, platforms may be arranged at any convenient angularorientation.

A platform may include an electrically conductive ground member disposedto provide a common electrical ground reference for a plurality ofswitches. A switch typically includes an electrically conductivedeflection member carrying a conductive area disposed in a substantiallyparallel arrangement relative to a portion of the ground member. Thedeflection member is placed in a normally spaced apart relationshipadapted to resist forming an electrically conductive contact between theground member and the conductive area, by a fastening arrangementdisposed at a perimeter of the deflection member operably to cause amembrane-bias in the deflection member effective to establish thenormally spaced apart relationship. The deflection member is structuredto permit deflection of a portion of itself in a direction effective toform the electrical contact under application of a switch activation, orclosing, force.

A dance platform typically includes nine zones arranged in threeadjacent rows of three zones per row, each individual zone comprising anactivation surface disposed individually to receive foot contact from auser, and the plurality of switches are disposed to locate one switch ateach of a selected number of the zones.

An operable deflection member includes an approximately square planarelement having four corners and carries a conductive area disposed on amembrane surface spanning between the corners. An operable ground memberincludes a planar element having a plurality of perforations disposed inharmony with at least the four corners of one deflection member when thedeflection member is in an assembled configuration, with a perforationbeing located at each corner of the one deflection member and sized topermit placement of a fastener operably therethrough to secure the onedeflection member in functional relation with respect to the groundmember.

In some embodiments of a platform, a fastener is placed in penetratingengagement through a corner of a deflection member. In other embodimentswithin contemplation, a fastener may be placed through bracket structureoperably to hold a plurality of deflection members. Certain perforationsin a ground element include edge structure operable as a fulcrum inharmony with an installed fastener to cause the membrane bias in adeflection member. A currently preferred fulcrum structure includes acorner button operable in combination with an installed fastener tocause a membrane bias in a deflection member.

It currently is preferred for a dance platform to carry a wire harnessincluding nine electrically conductive wires. The wire harness can bedisposed in a branched channel carried by a base member. At least onewire of the nine wires will generally have an exposed conductive portionarranged for compression contact on a conductive area of a deflectionmember. Desirably, the compression contact is caused by installation ofa fastener.

To improve reliability in certain environments, a contaminant resistantmembrane may be disposed substantially to cover the plurality ofswitches effective to resist passage of particulate matter to a normallyspaced-apart area between a deflection member and a ground member.

Sometimes, it is desirable to include a resilient element disposed in aload bearing path between a switch activation surface and a support fora platform. An operable resilient element can deflect responsive to afoot strike on an activation surface effectively to reduce repetitivecontact stress on a user.

In some cases, a platform may be used in combination with a tub adaptedto receive a bottom of the platform and configured to provide aload-bearing ramp edge disposed about a perimeter of the platform toaccommodate a difference in elevation between a top surface of theplatform and a platform support surface. Such a ramp is operable toresist twisting an ankle of a user who steps on the perimeter.Desirably, the tub further includes a friction enhancing interfacedisposed operably to resist movement of the platform relative to aplatform support surface. Sometimes the tub is adapted to dispose aresilient element for contact with a bottom of the platform and also toprovide a ramp edge disposed about a perimeter of the platform as aload-bearing transition between a top surface of the platform and a tubsupport surface.

To promote competition between a pair of users, a second platform may bedisposed side-by-side with a first platform. Typically, couplingstructure is provided and adapted for connection to both of the firstplatform and the second platform to maintain a substantially fixed andside-by-side orientation. One operable embodiment of coupling structureincludes spacing structure configured and arranged to maintain asubstantially fixed distance between two platforms. Desirably, thecoupling structure is removable from coupling engagement between thefirst and second platforms in a tool-free operation.

As a theft-reducing measure, dance platforms may used in combinationwith a security vault sized substantially to contain therein acommercially available game console, or controller, and providing one ormore access ports through which to place the game console in electricalcommunication with a platform and a video display device. Typically, thevault is disposed in tethered engagement to structure associated withthe platform.

Typically, an active dance platform according to the invention is usedin combination with a controller such as a commercially available gamecontroller. Such a controller includes a processor having an associatedmemory. The processor is adapted to receive an input from the pluralityof switches of the platform. A software instruction set is loaded intothe memory and configured to compare the platform input with a definedsequence of switch operation, and to display feedback for a user of theplatform on a video display device.

A platform having operable switches to produce a signal corresponding touser input may be regarded as an active platform. A user of an activeplatform may be regarded as a prime, or active, user. A practiceplatform may be defined as having structure, or elements, arrangedsubstantially to suggest portions of an operable activation surface ofan active platform, but generally is not connected to a controller toprovide user input to that controller. A user of a practice platform maybe regarded as a practice user. One or more practice platform can bedisposed on a support surface in harmony with a first active platformsuch that a practicing user, while operating a practice platform, mayreceive an input from a video display device used by the prime user.

A practice platform may include a rectangular display surface structuredto indicate a plurality of discrete zones, each zone corresponding to aswitch activation area of an active platform. Broadly, a rectangulararea includes a square area. One desirable practice platform includes afirst walkway and a second walkway, each walkway carrying a plurality ofzones and being structured cooperatively to form an interlockingarrangement in the shape of a cross for disposition of the cross on aload bearing support surface. An other operable practice platformincludes a plurality of discrete emblems disposable in a desired patternmaintained by a friction interface between a bottom of each of theemblems and a load bearing support surface, each of the emblemscorresponding to a switch activation area of an active platform.

The invention can be embodied as a standalone practice platform, adaptedfor use independent of connection to an electronic device. Such practiceplatform being structured to be visually representative of an activationsurface of a dance platform of the type including a plurality ofswitches disposed for individual activation by foot placements of a userstepping upon a selected portion of the activation surface of the danceplatform. In such an embodiment, an activation surface may include anapproximately square surface carrying indicia defining a plurality ofzones individually adapted to be visually representative of a selectedportion. In an alternative arrangement, an activation surface may beembodied as a cross formed by two interconnectable sidewalks, eachsidewalk carrying indicia defining a plurality of zones individuallyadapted to be visually representative of a selected portion. A secondalternative arrangement forming a practice activation surface includes aplurality of emblems adapted to be disposed in an arrangement on a loadbearing surface and thereby adapted to be visually representative of aselected portion.

A method of use of a system of dance and practice platforms typicallyincludes providing a first electrically active dance platform having aplurality of switches disposed for individual switch activation by footplacements of a user stepping upon a selected portion of the platform,the first platform being in electrical communication with a controldevice having a processor with an associated memory. The processor isgenerally adapted to receive an input from the plurality of switches ofthe first platform and includes a software instruction set loaded intothe memory and configured to compare the received input with a definedsequence of switch operation, and to display feedback for a prime userof the first platform on an associated video display device. One or morepractice platform is disposed on a support surface in harmony with thefirst platform such that a practicing user, while operating a practiceplatform, may also receive an input from the video display device, eachpractice platform being formed by elements arranged substantially tosuggest portions of an operable activation surface of the firstplatform. A first user of the system is placed in operable associationwith the first platform to form a first prime user. A second user of thesystem is placed in operable association with a practice platform as apractice user. The control device then outputs a signal to the videodisplay device for a proscribed first increment of time, during whichfirst increment of time the first prime user and the practice useroperate their respective platforms in accordance with instructionsdisplayed on the video display device.

Subsequent to elapse of the first increment of time, the method includescausing a rotation in position between users of the system effective toform a new prime user. Selection of new prime user may be based uponcompetitive performance of certain users, or a proscribed rotationpattern. The method may be extended by using the control device tooutput a signal to the video display device for a second proscribedincrement of time, during which second increment of time the new primeuser and a practice user operate their respective platforms inaccordance with instructions displayed on the video display device. Themethod may additionally be extended by repeating a rotation in positionbetween users, and using the controller to output a signal on the videodisplay for one or more subsequent increments of time.

These features, advantages, and alternative aspects of the presentinvention will be apparent to those skilled in the art from aconsideration of the following detailed description taken in combinationwith the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

In the drawings, which illustrate what are currently considered to bethe best modes for carrying out the invention:

FIG. 1 is an exploded assembly view of a dance platform structuredaccording to the invention;

FIG. 2 is the platform of FIG. 1, in partially assembled condition;

FIG. 3 is the platform of FIG. 2, in further stage of assembly;

FIG. 4 is an exploded detail view of structure assembled at the locationdenoted in FIG. 2 by arrows 4-4;

FIG. 5 is a cross-section taken through a portion of an assembledplatform;

FIG. 6 is an exploded assembly view of an alternative platformarrangement;

FIG. 7 is a top view of a portion of a platform;

FIG. 8 is a view in perspective of joining structure;

FIG. 9 is a top view of portions of two platforms in position to receivethe joining structure illustrated in FIG. 8;

FIG. 10 is a view in perspective of a platform and an associated theftresistant vault;

FIG. 11 is an exploded view in perspective of one embodiment of apractice platform;

FIG. 12 is a view in perspective of the platform illustrated in FIG. 1,in assembled condition; and

FIG. 13 is a top view of an exercise system including active andpractice platforms.

DETAILED DESCRIPTION

Reference will now be made to the drawings in which the various elementsof the illustrated embodiments will be given numerical designations andin which the invention will be discussed so as to enable one skilled inthe art to make and use the invention. It is to be understood that thefollowing description is only exemplary of the principles of the presentinvention, and should not be viewed as narrowing the claims whichfollow.

The invention can be embodied as a platform holding a plurality ofnormally-open electrical switches in position for closing a selectedswitch by applying a force, typically normal to a switch surface, with aportion of a human body. Such platforms may be used in a variety ofapplications, such as in various forms of physical therapy, and as danceplatforms of the type used in certain competitive games and forexercise, including group exercise. Certain platforms used in a therapyapplication may be structured for disposition of the platformvertically, horizontally, or at an intermediate angle, for activation ofa selected switch by a user's hands in accordance with a user input froman audio and/or a visual display device. A dance platform typically isdisposed on a load bearing surface for activation of a selected switchby contact with a foot of a standing user.

An exemplary dance platform, generally indicated at 50, is illustratedin FIG. 1. Dance platform 50 includes a base 53 which typically providesa channel structure 55 operable to hold a wire harness 57. Illustratedwire harness 57 typically includes nine individual insulated wiresconnected at one end to a conventional 9-pin serial connector 59.Channel structure 55 typically is branched to provide a run operable todispose terminal ends of certain wires of harness 57 at locationsdisposed over the base 53.

A base 53 can be made from a wide range of materials, with anonconductive material being preferred. It is currently preferred tomake a base 53 from a substantially square section of wood. Operablewood includes particle board, plywood, or solid wood. Plastic, rubber,urethane, and other materials capable of forming a load bearing surface,are also operable as a base 53. It is also desirable that a base 53 bestructured to receive and hold threaded fasteners.

During assembly of a platform 50, an electrically conductive element 63is disposed for support on top of a base 53 having an installed wireharness 57. A conductive element 63 serves as a common ground contactfor a plurality of switches, as will be described in detail below. Aplurality of perforations 67 generally are provided distributed about anelectrically conductive surface 71 of conductor 63. End portions of wireconductors carried by harness 57 are placed in electrical isolationthrough certain such perforations 67.

An operable conductive element 63 may be fashioned from a section ofsheet metal sized in general harmony with a size of base 53. Forexample, ground plate 63 may be made from mild steel sheet metal havingany practical gage thickness. It is currently preferred to make groundplate 63 from galvanized sheet metal having a thickness of about 28gage, and about 33 inches wide by about 33 inches tall, or so. It iswithin contemplation to make ground plate 63 from alternative structure,such as from expanded sheet metal, or even as an electrically conductivecoating applied to a base 53. Both ferrous and nonferrous metals areworkable to form a ground element 63. An operable ground member 63 canalternatively be made as a network of electrically connected patchesdisposed for association of one or more patches with a switching member.

Once the ground sheet 63 is placed on a base 53, corner buttons 75 canbe installed to hold the sheet 63 in place on the base 53. Withreference to FIG. 4, it is currently preferred to make a corner button75 from adhesive-backed hook-and-loop fastener material. The adhesivebacking of one portion 79 (either a hook-side or a loop-side) is placedat a plurality of strategic locations in overlapping contact with boththe ground element 63 and base 53. The cooperating portion 83 is thenapplied to the first portion 79, exposing a second adhesive surface 87to hold a corner 91 of a deflection member 95. Certain buttons 75 mayalso hold a terminal end 99 of a wire from harness 57 to place anexposed end of a wire's conductor for compression contact against corner91 upon installation of a fastener 103. Typically, an end 99 is coiledto place an uninsulated portion 100 of a wire conductor over a portionof the wire 101 that forms a coil (as illustrated in FIGS. 4 and 5), toensure electrical communication is made with a conductive area of aswitching member, such as deflection member 95.

As illustrated, a deflection member 95 may be structured as anapproximately square tile or plate, typically sized about 11 inches wideby about 11 inches tall in certain currently preferred dance platforms50. The member 95 carries an electrically conductive area disposed tomake switching contact with a cooperating portion of ground element 63.Desirably, a deflection member 95 is fashioned from a material havingresilience to bending and a memory to bias or restore a deflected suchmember 95 toward an original position. It currently is preferred to forman illustrated deflection member 95 from a square section of sheetmetal, such as galvanized mild steel, having a thickness of about 26gage.

A plurality of fasteners 103 are disposed about a perimeter of adeflection member 95 operably to hold the deflection member 95 infunctional position with respect to a base 53. As illustrated, onefastener 103 is placed at each of the four corners 91 of an illustrateddeflection member 95. However, it is within contemplation for a singlefastener 103 to be placed through a bracket structured to hold aplurality of corners. In such construction, a single fastener can secureone, two, or up to four corners, to speed assembly of a platform 50.

While fasteners 103 are illustrated as being threaded fasteners, otherarrangements are operable, including rivets, nails, bolts, and nuts. Itis preferred to use a fastening arrangement that can be removed, topermit servicing an assembled platform 50. Fasteners 103 desirablyoperate in harmony with fulcrum structure to cause a membrane-bias in adeflection member 95 operable to bow a center section of member 95 in adirection away from ground element 63. As illustrated, corner buttons 75operate as fulcrum structure cooperating with fasteners 103.Perforations 67 also, or alternatively, may be sized and disposed tooperate as fulcrum structure. In any case, the ground member 63 isstructured in harmony with the deflection members 95, such that aconductive path between them is not established by installation of thefasteners 103.

A switch portion, generally indicated at 107 in FIG. 5, of a platform 50includes ground member 63 and a deflection member 95. Such a switch isnormally-open, and is structured to be closed by a user's weighted footplacement to deflect a conductive area of member 95 into contact with acooperating portion of element 63.

In an alternative configuration to form a normally-closed switch,fulcrum structures are located at peripheral positions with respect tofasteners, effective to cause a membrane bias to deflect a centerportion of a deflection member into contact with a ground element. Sucha normally-closed switch may be actuated to an open position by a pushor pull member that is disposed to separate an electrically conductivecontact between the deflection member and ground element.

Commonly, indicia is placed over a switch 107 to indicate a footplacement position or zone (and generally, a corresponding underlyingswitch 107), to a user. As illustrated, a decal 111 may be used as suchindicia. A decal 111 may illustrate a shape, and/or a color. Indicia maybe painted, or applied as a film to member 95, or to a bottom surface ofa tile 115. Such indicia could be applied to a top surface of a tile115, but it is currently preferred to dispose a transparent barrierbetween the indicia and a stepped-on surface of the switch 107. Incertain embodiments of a switch 107, a tile 115 can alternatively beincorporated into a deflection member 95.

A tile 115 is generally structured to permit a transverse deflection ofa center membrane portion operable to deflect a corresponding membraneportion of deflection element 95 into contact with ground 63. A membranebias in deflection member 95, caused by fasteners 103 and fulcrumstructure, operates to restore the switch 107 to an open configurationsubsequent to removal of a user's weight. It has been determined that apolycarbonate plastic material sold under the trade name LEXANE™ andhaving a thickness of about 0.1 inches, is one material operable to forma rugged and long lasting tile 115.

In certain embodiments of the invention, a protective membrane 119 maybe included in a dance platform 50. When present, such a membrane 119 isarranged to resist passage of contaminant material, such as particulateor fluid matter, into a space 123 between ground plate 63 and deflectionmember 95. Plastic material, such as sold under the trade name LEXANE™and having a thickness of about 0.1 inches, is an operable material toform a protective membrane 119.

In a preferred method of manufacturing a platform 50, a plurality ofmanufacturing-assist jigs are used to facilitate alignment of individualcomponents of the platform. With reference again to FIG. 1, a preferredmanufacturing method includes placing a base 53 in a vertically orientedposition to receive a wiring harness 57 in channel structure 55. Groundplate 63 is then placed on top of the base 53 to expose terminal ends ofindividual wires at perforation locations 67. The ground member 63desirably is sized such that its perimeter edge may be aligned withstructure of the base 53.

A jigplate, having a size in accordance with the base 53, is used toplace a first portion of a plurality of adhesive-backed hook-and-loopfasteners 75 at desired locations in correspondence with corners oflater-installed tiles 115. A preferred such jigplate includes aplurality of second portions of hook-and-loop fasteners that areconfigured to cooperate with the first portions, and includes a reducedarea of hook-and-loop contact. Currently preferred hook-and-loopfasteners are round buttons with adhesive backing on each portion—boththe hook portion, and the loop portion. In any case, the shape of thefastener portions carried on the jigplate desirably corresponds with theshape of the portions to be installed, to facilitate placement of the tobe installed portions onto the jigplate. The reduced area ofhook-and-loop contact is sized large enough to hold the first portion ina desired position on the jigplate, but small enough to release thefirst portion from engagement with the second portion after the jigplateis placed into receiving position on top of the base 53. Then, thejigplate is removed, leaving behind a plurality of first portions in aplurality of desired installed positions effective to hold the groundelement 63 with respect to the base 53.

The cooperating portions of resilient elements 75 are then placed intomaking reception onto the installed first portions, and their adhesivebacking is exposed. The exposed adhesive backing facilitates placementof wire ends of the harness 57. Typically, the wire ends are coiled, asexplained previously, and an exposed portion of bare wire is located todrape over a coil, thereby forming a contact location between that wireand a subsequently installed switch plate 95. It is currently preferredto use an alignment jig that holds a plurality of rail elements defininga tic-tac-toe grid operable to space apart the metal tiles 95 and decals111. Such switch elements are simply dropped into receiving positionbetween spacing elements of the alignment jig, and may be secured withfasteners disposed at corner locations. Cover plates 115 may also beplaced at the same time, so long as no membrane 119 is installed in theparticular platform 50 that is under construction. If a membrane 119 isto be included, the alignment jig is removed while the membrane isplaced into position, then reinstalled to facilitate placement of thetop tiles 115 in a properly spaced apart conformation.

With reference now to FIG. 6, a dance platform advantageously may beassociated with shock-absorbing structure, such as resilient element127, operable to deflect responsive to a foot strike on an activationsurface of the platform 50, generally indicated at 131, effectively toreduce repetitive contact stress on a user. An operable resilientelement 127 is formed from a foam pad, such as part No. 55240, sold byFurniture/Mattress Supply Co., having a place of business at 16 WestCentral Ave. South Main, Murray, Utah 84107. A resilient element 127 canbe disposed anywhere in the load path from a user and between anactivation surface 131 and a load supporting surface 139. Theillustrated sheet of foam 127 sized for disposition under a platform 50is only one operable shock absorbing solution.

A platform 50 may also, or alternatively, be associated with a tub 135adapted to provide a load-bearing ramp edge 137 disposed about all or aportion of a perimeter of the platform 50. Desirably, the ramp edge 137is configured to accommodate a difference in elevation between a topsurface 131 and a platform support surface 139, thereby to resisttwisting an ankle of a user who steps on that perimeter. A tub 135desirably includes a friction enhancing interface to resist movement ofa contained platform 50 with respect to support surface 139. In certaincases, one or more corner brackets 140 and bracket fasteners 141 may beemployed to maintain a platform 50 in association with a tub 135.

At times, it is desirable to operate a pair of dance platforms 50 in afixed side-by-side configuration. One such situation arises duringoperation of the respective dance platforms by two competing users.FIGS. 7-9 illustrate details of one operable coupling structure adaptedto maintain a pair of platforms 50 in such a fixed side-by-sidearrangement. The coupling structure includes retaining structureassociated with a platform 50, such as one or more protruding bolt head143. Such retaining structure 143 may be affixed directly to a platform50, or to structure associated with a platform, such as a tub 135. Anexemplary spacer 147 may be formed from a length of metal having agenerally U-shaped cross-section, and a width indicated at D1. Slotstructure, generally indicated at 151, is disposed in downwardlyprojecting arms 155 to cooperate with the retaining structure 143. Asillustrated in FIG. 7, a space indicated at D2 is formed to accommodatestructure forming an arm 155.

With reference to FIG. 9, a first platform, generally indicated at 159,is placed into a side-by-side arrangement with a second platform,generally indicated at 163, to define a space 167 having a widthindicated at D3. The width D3 is sized in accordance with the width D1to permit a user to place spacer 147 into area 167 such that anengagement is formed between slots 151 and retaining structures 143.Such a coupling arrangement permits a tool-free removal of the spacingstructure 147. Alternative coupling structure within contemplationincludes spacer structure permanently associated with a respectiveplatform and structured removably to engage either with a secondplatform, or with structure associated with that second platform.

In general, a dance platform 50 is associated with a game controller 167to provide instructions and feedback to a user in a competitive game orexercise format. Sometimes it is desirable to secure the controller 167against loss by theft. One embodiment adapted to resist theft of acontroller 167 includes a theft resistant vault 171 sized to contain acommercially available game controller 167, such as a Play Station II,or an X-box. Illustrated vault 171 is sized to contain game controller167 at least substantially inside a space 175, and to provide one ormore access ports 179 through which to place the controller 167 intoelectrical communication with a platform 50. A typical such electricalcommunication is accomplished with a serial cable 183. Additional accessports 179 may be adapted to permit passage of cable 187 for connectionto a power source, and cable 191 for connection of controller 167 to avideo display device.

It sometimes is preferred to secure the vault 171 in tethered engagementto structure associated with a platform 50 to provide a theft resistantcombination. As illustrated in FIG. 10, a platform security cable 191 isconnected to a vault security cable 199 by way of lock 203. One end ofplatform security cable 191 is affixed to structure associated with theplatform 50, such as tub 135 or part of the platform 50 itself. An endof vault security cable is affixed to vault 171. An operable way toaffix respective cables to a platform 50 or vault 171 is to place a loopformed in a cable end through an aperture, and then to fasten an objecttoo large to pass through that aperture to the loop end. Operableobstruction objects include locks 203, and threaded chain quick-links.Of course other arrangements are operable to affix a security cable to aplatform 50 or vault 171, including welding, or the use of permanent orone-way fasteners. Certain such fasteners include pop rivets, fastenershaving heads that require specialized and uncommon tools, and fastenershaving heads adapted to engage a fastener-driving tool only in atightening direction.

Practice platforms can be used to advantage with active platforms 50 incertain circumstances. A practice platform generally is operated withthe practice platform placed in electrical isolation from a gamecontroller 167, but generally is disposed in proximity to a videodisplay device that provides input to a user who is operating thepractice platform. In most cases, a practice platform may be regarded asan inert device, in that no feedback for the practicing user is created.Practice platforms typically are low cost structures arranged tosimulate the activation surface of a dance platform 50. A user,operating a practice platform, typically will observe the input from avideo display device connected to an active platform 50, and canpractice, or rehearse the movements dictated by that video display. Aplurality of reduced cost practice platforms can be used in combinationwith one or more active platforms, to permit participation by a numberof individuals in an organized competition, or exercise routine.

FIGS. 11 and 12 illustrate one currently preferred practice platform 207adapted for partial disassembly to enhance portability and to providefor compact storage. Practice platform 207 includes a first walkway 211and a second walkway 215. The first and second walkways carrycooperating interlock structure 219 and 223, respectively, configured tohold one walkway in a fixed position with respect to the other walkway.On assembly to form a cross-like arrangement, as illustrated in FIG. 12,practice platform 207 provides structure operable to suggest zones, orstations for foot placements, representing the activation surface of adance platform 50. Walkway 215 carries emblem structure 227 and 231 toindicate a plurality of such zones. Walkway 211 carries emblem structure235 and 239, similarly to indicate a plurality of zones. A zone 243 incommon with walkway 211 and 215 is formed at the overlap area of thewalkways. Additional zones, including 247 and 251, are suggested atempty corner areas of the cross-like platform 207. If desired, one ormore discrete emblems suggesting corner structure of a platform 50 mayalso be placed in a corner zone 251, 247 of platform 207.

A walkway may be formed from any material having operable structuralproperties. For example, walkways 211 and 215 may be made from a plasticor from wood. Desirably, a thickness of the material forming a walkwayis sufficiently thin so that a user is not at risk of twisting an anklewhen stepping on an edge of the walkway's surface. A desirable thicknessis about ¼ inch, or less. It is currently preferred for a walkway 211 toinclude black arrows 235, 239 on a blue background 252. Also, walkway215 typically will include black arrows 227, 231 on a red background253.

It is within contemplation to form a practice platform from structurehaving alternative arrangements than the illustrated structure. Apractice platform must merely suggest the activation surface of anactive platform, such as platform 50. A workable practice platform caneven be formed by an active platform 50 that is not connected to a gamecontroller to provide feedback to the practicing user.

A functional practice platform may be formed by placing discrete emblemsin an arrangement on a load bearing surface to suggest an activationsurface of a dance platform. An operational discrete emblem may beformed from a suitably thin material to suggest the shape of an arrow orsimply a colored shape, and oriented on a load bearing surface torepresent an emblem such as emblem 231, or 239, or at an angle torepresent a corner zone 251. It is desirable for the discrete emblems tohave an operable friction interface with the load bearing surfaceeffective substantially to maintain a position of the emblems duringoperation of the practice platform.

An alternative practice platform can be formed as pictorialrepresentations on a roll-up rectangular sheet of material, such as aplastic membrane or a cloth-like material. The surface of a practiceplatform can be rectangular, approximately square, cross-like, or anyother shape, so long as a visual appearance effected by the practiceplatform suggests an activation surface of an active platform.Preferably, the practice platform includes designated spaces incorrespondence with the four arrow locations of a commercial embodimentof a DDR dance platform. It also is within contemplation to form apractice platform in the approximate shape of an octagon. Such anoctagon shape may be formed by trimming certain corners of a square atabout a 45 degree angle, or by removing portions from one, two, three,or four corners of a theoretical starting square. The material removedin such theoretical transformation can include a radiussed portion,somewhat like a stylized shape of an icecream cone.

FIG. 13 illustrates a pair of active platforms 255 and 259 connected toa controller 167 in an arrangement to permit competitive operation ofthe platforms. A first active user 263 is operating active platform 255in accordance with instructions displayed on video display 267. A secondactive user 271 is operating active dance platform 259. In certaininstances, an active user may be regarded as a prime user. A pluralityof practice users 275 are illustrated operating a plurality of inert, orpassive practice platforms 207 disposed to permit the practice users 275to observe the display device 267. In certain cases, controller 167 canbe adapted to output two sets of instructions on a display screen 267 atthe same time, and to score a user in accordance with each output. Insuch cases, one instruction set may be at a more advanced level than theother, to permit participation of users having a plurality of abilitylevels.

One way to operate the system illustrated in FIG. 13 is as follows: Afirst user is placed into operable association with the first platform255 to form a first prime user 263. A second user 279 is placed intooperable association with a practice platform 283 as a practice user. Acontroller 167 is used to output a signal to video display device 267for a proscribed first increment of time, such as for the duration of asong. During that first increment of time, the first prime user 263, thepractice user 279 (and other users 271, 279 if present), operate theirrespective platforms in accordance with instructions displayed on videodisplay device 267. Subsequent to elapse of the first increment of time,a rotation in position between users of the system typically occurseffective to form a new prime user and the prime user 263 may be rotatedto a practice position. The controller 167 may then display instructionson device 267 corresponding to the same or a new song, or instructionset. When two prime users 263, 271 are present, the prime user who“wins” (best matches the foot placements in correspondence to theplacements proscribed by controller 167), may remain as a prime user,and the “losing” prime user may rotate to a practice user position. Inan alternative method of use, both prime users 263, 271 may rotate to bereplaced by a pair of practice users 271 or 279 subsequent to havingtheir “turn” as prime users.

While the invention has been described in particular with reference tocertain illustrated embodiments, such is not intended to limit the scopeof the invention. The present invention may be embodied in otherspecific forms without departing from its spirit or essentialcharacteristics. The described embodiments are generally to beconsidered only as illustrative and not restrictive. The scope of theinvention is, therefore, indicated by the appended claims rather than bythe foregoing description. All changes which come within the meaning andrange of equivalency of the claims are to be embraced within theirscope.

1. In a rigid platform of the type used in machine dance activity andhaving a substantially planar top surface defining an area bounded by aperimeter, with the top surface being spaced apart in a verticaldirection from a support surface, the platform including a plurality ofswitches disposed for actuation of the switches by a stepping action ofa user's foot, the improvement comprising: a resilient element disposedin a load bearing path between said top surface and said supportsurface, said resilient element being operable to deflect responsive toa foot strike on said top surface effectively to reduce repetitivecontact stress imparted to a user, wherein: said resilient element isdisposed beneath all switch structure and above said support surface. 2.The improvement according to claim 1, further comprising: a frictionenhancing element disposed for contact with said support surface andeffective to resist transverse displacement of said platform during usein said machine dance activity.
 3. The improvement according to claim 2,wherein: said friction enhancing element is operable to deflectresponsive to a foot strike on said top surface effectively to reducerepetitive contact stress on a user.
 4. The improvement according toclaim 1, wherein: said resilient element comprises a shock-absorbingstructure sized in substantial agreement with a size of said planar topsurface.
 5. The improvement according to claim 4, wherein: saidshock-absorbing structure comprises a foam pad.
 6. The improvementaccording to claim 5, wherein: said foam pad has a substantially uniformresilience throughout.
 7. In a rigid platform of the type used inmachine dance activity and having a substantially planar top surfacedefining an area bounded by a perimeter, with the top surface beingspaced apart in a vertical direction from a support surface, theplatform including a plurality of switches disposed for actuation of theswitches by a stepping action of a user's foot, the improvementcomprising: a resilient element disposed in a load bearing path betweensaid top surface and said support surface, said resilient element beingoperable to deflect responsive to a foot strike on said top surfaceeffectively to reduce repetitive contact stress imparted to a user;wherein; said resilient element is configured and arranged for removableassociation with said platform by a user; and said resilient elementcomprises a tub configured for drop-in reception of said platform.
 8. Ina platform of the type used in machine dance activity and having asubstantially planar top surface spaced apart in a vertical directionfrom a platform support surface, the platform including a plurality ofswitches disposed for actuation of the switches by a stepping action ofa user's foot, the improvement comprising: a resilient element operableto deflect responsive to a foot strike on said top surface effectivelyto reduce repetitive contact stress imparted to a user, said resilientelement being disposed in a load bearing path defined in a platformdisposed in a conventional horizontal use position and starting beneathswitch structure of said platform and extending to said platform supportsurface.
 9. The improvement according to claim 8, wherein: saidresilient element is configured and arranged for removable associationwith said platform by a user.
 10. The improvement according to claim 9,wherein: said resilient element comprises a tub configured for drop-inreception of said platform.
 11. The improvement according to claim 10,said tub further comprising: a ramp edge disposed around a perimeter ofsaid platform and configured to accommodate a difference in elevationbetween said top surface and said platform support surface, thereby toresist twisting an ankle of a user who steps on that perimeter.
 12. Theimprovement according to claim 10, said tub further comprising: afriction enhancing element disposed for contact with said supportsurface and effective to resist transverse displacement of said platformduring use in said machine dance activity.
 13. The improvement accordingto claim 9, wherein: said resilient element comprises a shock-absorbingstructure sized in substantial agreement with a size of said planar topsurface.
 14. The improvement according to claim 13, wherein: saidshock-absorbing structure comprises a foam pad.
 15. The improvementaccording to claim 14, wherein: said foam pad has a substantiallyuniform resilience throughout.